If this is your first visit, be sure to
check out the FAQ by clicking the
link above. You may have to register
before you can post: click the register link above to proceed. To start viewing messages,
select the forum that you want to visit from the selection below.

Re: Computer, OS and Scanner Survey

Originally Posted by Nodda Duma

Sorry, 2.5 GHz. Typo.

Yes, there is overhead naturally, but performance testing (number of ray traces per second) that I did while justifying computer upgrades to management indicated close enough correlation that I can claim "double the speed with double the processor.

Lens design software does not currently take advantage of GPU's. Ray tracing is only a small part of optimization. Most of an optimization cycle involves adjusting defined parameter variables and determining the effect on the value of an RSS Merit Function. The merit function can consist of thousands of calculations of performance characteristics defined by the designer such as aberration correction, mass, overall length, focal length, wavefront error or spot size, etc, etc. It's a very complex and very large set of mathematically intensive calculations.

I have talked to folks at Zemax about using the GPU. They've said in the past they were looking into it, but nothing has ever come of it. An actual ray trace through the optical system is actually pretty simple and fast. My guess is the gain in speed is not worth the trouble involved in supporting all the different GPUs out there. But I'm not a software guy.

Thanks for the additional information, but I'm still really curious about what sounds like a really nice set-up.

I'm guessing you're running dual processors, but Intel doesn't even make a 16 core at 2.5gz. Are you by chance counting virtual cores in your 32? 2x8 core Xeons(w/HT) at 2.5ghz is much easier combo to find

Also, I'm REALLY surprised that they haven't jumped on using the GPU for calculations. Many of the calculations you describe would be right at home on a GPU and it could cut computation times dramatically. You don't necessarily HAVE to write code for every GPU, but none the less they could optimize for a specific GPU family and just specify that. I suspect that anyone who's buying a 32 core workstation wouldn't mind dropping another $1K on a GPU if it meant cutting the times to do the calculations in half(or better).

Past about 4 CPU cores or so, you can really get into diminishing returns on how much each additional core helps speed things up.

Re: Computer, OS and Scanner Survey

Early 2008 Mac Pro (upgraded with lots of memory, an SSD, and a better graphics card than the stock one it had originally) running El Capitan, Epson V700.

The Pro is still cranking along, albeit finally left behind in the constant march of OS, uh, progress. There are tricks for upgrading the 3,1 to Sierra, but I can't really be bothered; it's time to finally replace it, once Apple gets around to telling us what they're doing about new Pros. I can hang on until then -- although for a while I was starting to wonder if I could.

Re: Computer, OS and Scanner Survey

Originally Posted by Robert Brazile

Early 2008 Mac Pro (upgraded with lots of memory, an SSD, and a better graphics card than the stock one it had originally) running El Capitan, Epson V700.

The Pro is still cranking along, albeit finally left behind in the constant march of OS, uh, progress. There are tricks for upgrading the 3,1 to Sierra, but I can't really be bothered; it's time to finally replace it, once Apple gets around to telling us what they're doing about new Pros. I can hang on until then -- although for a while I was starting to wonder if I could.

Robert

Apple actually had an uncharacteristically frank and open discussion last week about the future of the MP line. They basically acknowledged how badly they messed things up with the traschcan, and are promising a ground up re-design that actually allows for user expansion sometime in 2018. It remains to be what form it will take, but I have high hopes that it will be better than the current Cube 2.0.

My MP 1,1(now fully upgraded to 2,1 specs) hit a brick wall with Sierra since the CPUs don't support the instruction set needed(SSE4). The 3,1 are a bit of a "soft" block, although they it's not as simple as just bypassing system requirement checks like installing Leopard on many unsupported G4s. Fortunately, given Apples historic trends, El Capitan should be receive security updates into the fall of 2018, by which point hopefully the new MP should be out.

Re: Computer, OS and Scanner Survey

Mac Tower 1999 (G4), Mac Cinema HD screen, Screen Cezanne scanner. I move files via a Firewire disk that is itself over 10 years old.
My main computer these days is a MacBook Air with another Mac Cinema HD Screen, and several external Hds.